Gun cooling valve



Jan. 26, 1960 G. A. HAwKlNs GUN COOLING VALVE 2 Sheets-Sheet 1 Filed Nov. 3G, 1945 liu. fiinlllnllnlml l l l Ill Geur e A Hawkn Jan. 26, 1960 G. A. HAwKlNs GUN COOLING VALVE 2 Sheets-Sheet 2 Filed NOV. 3G, 1945 3mm/vbo@ Geur e A l'awkn 2,922,339 Patented Jan. 26, 1960 GUN COOLING VALVE Application November 30, 1945, Serial No. 632,068

4 Claims. (Cl. 89-1) The invention relates to means for injecting water or other liquid into the chamber of a gun, operable by a conventional recoiling part of the gun; and particularly to means adapted to use on high speed machine guns such as the current models of .30 caliber and .50 caliber machine guns. An important purpose is to present a valve for delivering charges of cooling liquid to the gun, so constructed as to be readily incorporated on guns already manufactured without change of construction of the firing mechanism, and without impairing the action and efficiency of the arm. Also, it is sought to enable the operation of such weapon in the usual way, and with a minimum requirement of special service. Additional requirements which it is an aim to meet are: Lightness, compactness, durability and ruggedness, ready accessibility to parts and avoidance of interference with usual servicing and repair of the standard gun action. Y

Y It is particularly an aim to enable the operation of the invention by a recoiling part of the gun in such manner that the rate of fire will not be materially slowed, and whereby energy of recoil heretofore dissipated may be converted to the operation of the device of my invention. On account of the fact that the work required of the firing mechanism is in many cases close to the maximum for which energy is available, it is an important purpose to minimize requirements of power for operation of the device.

It is a specific object of the inventor to present a device which will supply a measured charge of liquid to the chamber of a gun after the firing of each round at the short intervals of time involved in machine gun re.

A further important end in View is to develop a device which will store part of the recoil energy of the wea-pon and convert it to counter recoil force acting on the valve to return it to an initial position after recoil.

Additional objects, advantages and features of invention reside in the construction, arrangement and combination of parts involved in the embodiment of the invention, as will be apparent or understood from the following description and accompanying drawings where- 1n;

Figure 1 is a left side elevation partly in section of the rear part of a gun upon which my invention has been incorporated;

Figure 2 is a cross section of the pump on the line 2 2 of Figure 1;

Figure 3 is an elevation of the left side of a gun having a modified valve thereon;

Figure 4f is a top view of the gun and valve modification partly in section;

Figure 5 is a section on the line 5 5 of Figure 3;

Figure ',6'is a section on the line 6 6 of Figure 3; i Figure] isa section on the line 7 7 of Figure 3; "Figure`-8is`a'rear-view of Vthe bolt yof Fig.` 1;.v

Figure 9 is a fragmentary longitudinal section of a modified valve, alone.

Referring more particulary to the details in the drawings, there is illustrated in Fig. l a conventional machine gun 10 having a barrel 70 with a chamber 71, receiver body or case 11, at the rear end of which grips 12 familiar in this gun are mounted on a back plate 13 of the receiver. At the upper part of the back plate a trigger 14 is mounted, operable between the grips as heretofore.

The back plate 13 has the usual buffer disc sleeve 15 in which elastic buffer discs have heretofore been mounted supported rigidly at the rear or outer end of the sleeve, and bearing against a buffer plate set in Ithe back yplate and rearwardly yieldable to the bolt of the gun action, a form of which may be found in the patent-to Browning 1,628,226. Equivalents of the discs are retained as at 16 and a buffer plate 17 mounted as before, but all the discs and the buffer plate are axially bored, so as to receive freely slidable therethrough a valve stem 18 extending through the head 19 of a valve case or cylinder 20, the head being tenoned and threaded to screw into the rear interiorly threaded end of the sleeve 15 and against the discs as a rigid support or seat therefor. The tenon 21 is bored at its forward end to receive a packing and gland around the stem 18, at 22, the stem 18 being snugly slidable through a reduced bore in the head. A spool valve 23 is fixed on the stem, and reciprocable in the-cylinder 20. In the present instance the cylinder is shown as a bored piece closed at its rear end. The length of the cylinder bore greatly exceeds the length of the required stroke of the valve, so as to accommodate a spring of adequate length. Y

The valve body-23 is held between nuts 23 screwed on to and set with Ithe rear end portion of the stem 18 so as to be longitudinally adjustable on the stem. The valve is formed with a relieved part 24 intermediately of its length, extending entirely around the valve, its longitudinal extent being nearly equal to the maximum stroke of the valve, as will appear, leaving a cylindrical head or land 25 at the rear end, and a similar land 25 at the forward end. Land 25 engages the head 19 to limit the normal forward or initial position of the valve. The valve is urged to its initial forward position bv a spring 26 confined between the rear end of thevalve and a screw plug 27 engaged inthe rear end of the tube 20. This plug may be used to adjust the tension on the spring 26 if desired. It is cup-shaped, to receive the end of the spring a distance thereinso that the tube is not required to extend overk the entire length of the spring. The plug has a vent port 28 therethrough by which air and leakage water may be vented in operation of the valve.

Inlet and outlet ports 30 andV 31 are formed in opposite sides of the tube 20, located so as to be midway of the length of the land 25 when the valve is at initial position. VVA forward vent port 32 is formed in the lower side of the tube at its forward extremity, and this port 32 may be reduced in size, if desired, to serve as a dash pot control function.

The stem 18 is in line with a part of the usual bolt 33 of the gun mechanism, and on the rear end of the bolt a striker plate 34 is mounted by means of a transverse dovetail slide bar 3S set slidably in a corresponding horizontal channel formed across the rear end, of the bolt and fitted at its ends slidingly between the side plates of the receiver 11. In consequence, the plate 34 is held in operative position without fastening as long as the bolt is in place in the receiver: The stem 18 is extended a distance forwardly of buffer plate 17in the pathfof the bolt sufficient for the latter to engage it and move Vofver the greater part of its travel. h Y my valve may tendto slow the bolt slightly due to thel the valve land 25 past the ports 30 and 31 a distance corresponding to the time during which it is desired to keep these ports open. This time is limited at its minimum bythe time of .recoil'of the bolt over., the distance which the valve has been moved and at its'maximum by the extent ofV movement `of the bolt in operating the valve and the timerrequired for the spring 26, to return the valve to initial position, if this return movement'is slower than that of the bolt. l

A supply pipe 36 is connected to the inlet port 30 and a delivery pipe 37 is extendedfrom the outlet port 31 tothe chamber 71 of the barrel 70,where the liquid delivered, as generally indicated by reference numeral 72, maybe utilized inaccordance with approved methods and in suitablerapparatus for cooling the chamberand bore of the gurl.` These features comprise no 4novel part, ofthe present invention and thereforerare not illustrated,

In the use of .this invention a source 64 of liquid under. pressure is provided fronrwhichfthe supply duct 36 is led to the inlet port of the valve. This source may be reservoir with air chamber 65 and compressor 66, and is maintained at a pressure proportionate to the size. of orifice of the jet at the gun chamber, the time within which a required quantity of liquid must be forced through the jet, and inertia and friction of the..water column to be moved. These pressures may Vary from p.s.i. to 600 p.s.i. The quantity of water required may b e three cubic centimeters per charge, more or less, according to the degree of cooling desired and the temperature of the liquid supply.

For a .50 caliber machine gun three and one half cc. or less, have been found effective.

The bolt 3310i the iring mechanism of` theigun in- I dicated travels a distance of approximately seven and one eighth inches, and the valve 23 is adjusted so that itsV stem will be engaged during the extreme terminal part of the recoil movement of the bolt. The valve parts and nozzle are so proportioned that, with a pressure water supply within the range of pressures indicated, the necessary quantity of water may be forced through the ports 30 and 31 while the valve is moving from initial open position to extreme rearward position and back again to cut off.

As this extent of movement of the bolt occurs in something like goOO second, at usual rates of antiaircraft fire, spring 26 may, if desired, be made of such strength that it willreturn the ,valve more slowly than theA bolt travels by reboundfrom the buffer plate and propulsion of its driving spring. But thisY slower return movement is sufiicient to close the ports 30 and 31 before completion of counter recoil of the bolt to that point wherethe new cartridge has been entered so far as to interfere with the water jet.v i

In the type of gun mentioned a recoil action separate fromthat of the bolt is provided for the barrel, operatively connected with the cartridgefeeding means, the extentY of travel of this recoil beingl only aboutone andv one eighth inches; and the bolt, yutilized for the loading, firing and extracting and cocking, moves independently The operation` of energy applied thereto. However, there is an initial recoil and terminal counter recoil interacton and coupling between the barrel unit and the bolt unit, including an accelerator device on the barrel unit by which impetus may be added to the movement of the bolt, and counter` recoil functions vof the barrel unit are adjustablesolthatr an increment of velocitymay be added to the boltrmovement'to compensate for the energy; required in operating sfisgtig-meipnsae The es' are, reisewetter;

from the receiver sufficiently toA be utilized in the operation of the fvalve. For this purpose a guide 43 is secured to the side plate of the receiver, having a channel 46 on its under side over the slot 40 in which a slide 44 is reciprocably engaged. This slide has a longitudinal slot 45 therein receiving the end of the stud 42 for longitudinal movement along the slot 45 and against the ends of the slot. This slot 45 is shorter than the travel of the bolt of the gun, and is proportioned so as to be engaged at its rear end by the stud 42'while the bolt is moving rearward in extraction of the fired cartridge case from the gun chamber. The guide 43 has ,a slot 47 open throughV its left side and forward end over the channel 46,y and extending over a distance which is more than the difference between the length of the slot 45 and travel of the bolt.

A valve case 48 is fixed with the guide 43, having a horizontal cylindrical bore 54 therein open at its forwardend. On the Yforward part of theslide 44, a lug 49 is formed extendedV outward through the slot 47 across the axis of the bore 54 and has inserted therethrough a threaded tenon 50 of a valve member. 50, which consists of a rectilinear bar extended rearwardly from the lug 49. It includes a large diameter base stem part 51 which remains without the case and has a seat shoulder 52 thereon, a helical Wire return spring 53 beingpengaged around the part 51 and confined between the seat 52 and the forward end of the case 48. A distance rearward of this seat, the valve bodyY is reduced to the diameter of the bore 54 forming a land 55, which slidably tits, and remains engaged in, the bore 54 throughout operative movements of thevalve. v Rearward of the land 55 a circumferential relieved part 56 of the valve extends over a distance equal to the travel of the Valve, affording a clearance or annular channel 56' within the bore, and this terminates at a rear end land 57 fitted to the bore 54v slidably.

With the part described proportioned and arranged, as shown, the land 57 will have an extreme operated position adjacent the rear end of the bore 54 in the case 48 and an initial, forward closed position with the land 55 extending a distance into the bore 54. At a point in-V termediately of the rear land 57 while at its stated initial position an inlet port 58 is formed through the case to the bore54 and an opposite outletport 59 is formed from the bore 54 through the case, into which is connected a Vdischarge pipe 60 which is extended forwardly beside thegun to whatever device there maybe used for introducing discharged liquid into the chamber 71 of barrel 70 of the gunas generally indicated by reference numeral 72. The details thereof are omitted in the present application -since they form no part of the invention here claimed. A high pressure liquid supply conduit 61 is connected into the inlet port 58 of the valveA case, leading from any suitable pressure liquid supply not shown, but which may correspond to the source 64 before described.

For the purpose of enabling some adjustment of the timing of the function of the valve the valve maybe made adjustable longitudinally on the'lug 49, nuts. 62

being 'engaged and adjustable on the tenon 50 on each side of the lug 49.

A bumper or stop 67' isprovided at theforward end of the channel 43, against which the slide 44 may engage when at the forward limit of its movement. This may be aV separately attached piece or a part of the guidey 43.

Figure 9 illustrates the valve case 20 constructed with the inlet port30 longitudinally forward of the outlet 31 so'as vto lie just forward of the rear land of the valve when the latter isat the forward limit of its movement deningits 'initialposition The outlet port 31 is still midway of the rear land ofthevalve 273, at this position. This arrangement effects better Abalrrncing"ofthe 3 valve, pressures being equal on all sides and against the inner faces of both lands.

In the rear end of the case a vent port 63, shown in Figs. 3 and 4, is formed therein at the lower side to relieve air pressure and drain leakage liquid from the bore behind the valve, and to function otherwise as in the case of the port 32 before described.

In the operation of the gun equipped with my invention, in the reciprocation of the bolt, when it moves in recoil from battery position, it extracts the empty cartridge case, drawing the same rearwardly from the chamber of the gun. Before the case clears the chamber it is intended that the bolt stud 42 shall engage the rear end of the slot 45 and thereby move the land 57 clear of the ports 58-59. The bolt then has a further recoil` movement carrying the empty cartridge case and valve with it. After the cartridge case is ejected, a further recoil movement of the bolt occurs, still moving the valve, by which movement also a new round is extracted from the cartridge belt, preparatory to its being thrust forward into the empty chamber. The valve will then be at its rear limit or full stroke operated position. The bolt 'now counter recoils, and performs this loading function. The length of the slot 45 is such that the bolt stud engages the forward end of this slot 45 while the point of the round is entering the chamber, or shortly before, so that the rear land 57 is moved forward, and will be returned to cut-off relation with the ports 5859 while the round is partly entered in the chamber. By utilizing the maximum possible time during movement of the bolt to keep the valve open, the requirement of pressure in the supply is minimized, and a good jet function made possible with low pressure in case such a de- Vice is used at the gun chamber.

While I have disclosed the invention in detail in its best construction perfected and used by me, it will nevertheless be understood that this is purely exemplary and that modification of construction, proportions and arrangements of parts, substitution of materials and equivalent mechanical or otherwise, fall within the spirit of the invention in consonance with the appended claims, wherein I claim:

1. The combination of a machine gun of the character described and a bolt-operated water injection control valve comprising a gun framing, a bolt reciprocable therein, a guide parallel to the bolt path externally of the framing, said bolt having a stud projecting laterally therefrom exteriorly of the framing, a slide reciprocable in the guide having a part in the path of the stud rearwardly of the latter, a spring to return the slide to a forward initial position, means to limit forward movement of the slide, a case cylinder fixed with the framing parallel to the guide, a valve reciprocable therein having a stem part extended forwardly from the cylinder, a lug fixed on the slide across the axis of the case, said stern being fixed to the lug, an inlet port formed in the case forwardly of the rear part of the valve when at initial position, a high pressure liquid supply connected therewith, an outlet port formed in the case spaced from the inlet port and located intermediately of the rear portion of the valve when the latter is at said position, and a discharge conduit from the outlet port to the gun chamber.

2. In an automatic firearm having a receiver body, a barrel aixed thereto, and a bolt slidable therein in recoil and counterrecoil, a cooling system for said barrel cornprising a valve case affixed to said body parallel with said bolt, diametrically opposed inlet and outlet ports provided in said case, said inlet port connected with a high pressure coolant source, said outlet port communicating with said barrel, a spool type valve slidable within said case and having lands formed at each end thereof, the rearward land normally resting adjacent said diametrically opposed ports, spring means biasing said valve forwardly, a valve stem connected with said valve and extending forwardly of said valve case externally thereof, the said bolt being operative in lost motion relationship with said stem to move said stern rearwardly during the latter part of the bolt recoil stroke, the distance between said lands being substantially equal to the said operative portion of said bolt stroke, the system being operative to spray a coolant into said barrel in the interval between rst round red and second round inserted into said barrel.

3. The invention according to claim 1 wherein the said inlet port is formed in said cylinder case in diametric opposition to said outlet port.

4. The invention according to claim 1 wherein an elongated slot is provided within said slide, said lug adapted to rest normally against the forward end of said slot and to engage the rearward end of said slot during the latter part of the bolt recoil stroke.

References Cited in the file of this patent UNITED STATES PATENTS 543,567 Browning July 30, 1895 1,007,743 Smith Nov. 7, 1911 1,073,452 White Sept. 16, 1913 1,398,452 Wagnon Nov. 29, 1921 2,416,768 Monnet' Mar. 4, 1947 2,427,374 Walker Sept. 16, 1947 2,641,162 Ballesisen June 9, 1954 FOREIGN PATENTS 21,546 Great Britain 1896 

